not sure how much fun anyone would be when they have been left to oversee a major corporation (with the original demon boss)...and it seems to be collapsing in ruins around them._________________aka: neverscared!

I hardly think that one incident with one Fembot qualifies as "collapsing in ruins."

The Sunday strips which allege that Jesus and Blue attended divinity school together (which would mean that Blue is, like Jesus, over two thousand years old (although the fact that the divinity school sequences apparently occur before The Devil "fell from Heaven" would seem to imply that they occurred MUCH longer ago than two thousand years)) add an extra little je ne se quais to the posted sequence -- to, in fact, every interaction Jesus and Blue have ever had (which mostly consists of Jesus transforming Blue (and Fuchsia) into mortals without their consent, of physically and mentally violating them without so much as a by your leave, much like The Devil did Tange) -- but since I don't much care for the divinity school strips, I'll leave further commentary on the matter to someone else.

Well, there is a character from Paradise Lost that is noticably absent in Sinfest that could have Blue as a stand-in, although I personally doubt that is in anyway the author's intent. The first female-gendered entity in Paradise Lost is not Eve, it is Sin, daughter of Lucifer.

Rough order of events regarding Sin:

-Satan, still an angel, defies god.
-Sin emerges fully-formed from Satan's forehead, much like how Athena emerged fully-formed from Zeus. Physically she resembles a female angelic Satan. Satan and Sin immediately fuck.
-Satan and his rebel army get their asses handed to them by Jesus and Michael the Archangel and are banished from Heaven, through Chaos, and into Hell. Here they begin to physically resemble demons.
-Sin is assigned by God to guard the entrance to hell and is given the key to the gate. Pregnant from her intercourse with Satan she gives birth to Death, who violently rips himself out of her.
-Death rapes sin, causing her to be pregnant again, and give birth to monstrous demonic spawn who inhabit hell, and sometimes also rape or cannibalize their immortal mother.
-Satan and Sin re-unite and Sin gives him the key to Hellgate, making her the worst choice for a gate-guardian ever.

She's not mentioned after that and is clearly meant to be a symbolic character within the context of Paradise Lost, as was commonly done in morality plays and narratives in that time. I never really expect her to show up in Sinfest since her fate in Paradise Lost is very NSFW and at best she'd just be a female distaff-character of Satan. Also, were she introduced, the title would suddenly become eponymous.